Sustainable aviation fuel (SAF) is a biofuel that has properties similar to conventional jet fuel with reduced life cycle greenhouse gas (GHG) emissions, or carbon intensity (CI). SAF’s low CI provides a solution to reducing aviation GHGs that make up 9 to 12% of U.S. transportation GHG emissions. SAF created from renewable biomass and waste resources has the potential to deliver the performance of petroleum-based jet fuel but with a fraction of its carbon footprint.

Biomass is a renewable organic resource that includes agriculture crop residues, forest residues, crops grown for energy use, organic municipal solid waste, and animal wastes. Growing biomass removes CO₂ from the atmosphere which means the net carbon emissions are low, especially when coupled with carbon capture and sequestration (CCS). Gasification and pyrolysis are routes to the conversion of biomass to SAF. Gasification process converts organic or fossil-based carbonaceous materials to carbon monoxide and other gases. A water-gas shift reaction is utilized to react the CO with water to form CO₂ and hydrogen. Absorbers or special membranes separate the hydrogen from the gas stream. Recycled carbon can react with renewable hydrogen to increase the production of renewable fuel. 

Producing SAF from renewable and waste resources creates economic opportunities in farming communities, improves the environment, and boosts aircraft performance. SAF burns cleaner in aircraft engines as it contains fewer aromatic components, reducing the impact of contrails on climate change. As a result, there are lower local emissions around airports. Furthermore, the production of biofuels contributes to the domestic economy by creating jobs, forging new economic benefits.

Prepared by Stefan Unnasch and Kathleen Dailey
Life Cycle Associates, LLC